Comparison of non-linear finite element stress analysis with in vitro strain gauge measurements on a morse taper implant

Purpose: To understand the mechanical and biomechanical behavior of dental implants, validation of stress and strain measurements is required. The objective of this study was to compare a non-linear finite element stress analysis with in vitro strain gauge measurements on strains in an implant-abutment complex. Materials and Methods: Strain gauges were bonded to an implant-abutment complex and embedded in polymethylmethacrylate resin. A force of 75 N was applied vertically and laterally in separate load cases, and strains were recorded with a strain indicator. Then, a finite element model of the strain gauge model was constructed. Contact analysis with normal contact detection and separation behavior was performed between the implant and the abutment. The same loading protocol was followed, and strains were recorded at regions where gauges were bonded. Results: Under vertical loading, the qualification and quantification of strains were similar in both methods. Under lateral loading, the measurement of strains on the abutment and in the resin were similar in both methods. However, strains on the implant collar as measured by non-linear finite element analysis were higher. Discussion and Conclusion: There is a compatibility between non-linear finite element stress analysis and in vitro strain gauge analysis on the measurement of strains under vertical loading. However, there are differences between the methods in the quantification of strains on the collar of implants under lateral loading.